Inside the world’s most intense stag do ‘torture’ experiences where ‘victims’ are electrocuted, waterboarded and have ‘used’ TAMPONS stuffed in their mouths

But while US-based “haunts” are the perfect place to prank a groom-to-be on a stag night – be aware that these “extreme” shows are not for the faint-hearted.

Among the most notorious examples is The Victim Experience in Las Vegas where guests have to sign a waiver to take part.

On its website, the show warns that it will use electricity, drowning and suffocation to scare the living hell of its customers.

Special effects and professional foul-mouthed actors are used to frighten paying guests who are bound and gagged.

The experience also warns that “extreme simulated death scenarios” are used in the psychological rollercoaster.

Electrified fences and objects similar to stun guns are used to coerce fright fans.

The actors taking part are said to verbally abuse participants from the moment the show starts.

Fighting back or resisting is forbidden and ends the experience immediately.

8 A very sinister looking man grabs a woman by the throat during the experience8 A woman is grabbed from behind during her 'experience' at Heretic House in LA – however the woman is complicit and is able to stop the experience at any timeInstagram / @theblackoutexperience8 The Black Out Experience in California uses water and electricity to scare customers

Such events borrow from so-called “torture porn” movies such as the Saw and Hostel horror franchises.

Another “haunt” experience is Blackout, located in both Los Angeles and San Francisco, where guests are again required to sign legal waivers.

Among the tactics used by the event’s scare masters is dunking participants in water and shoving tampons, which have been soaked in fake blood, into their mouths.

Those taking part are also made to walk barefoot over a floor covered in squelchy “used” condoms.

Simulated sex is also performed in a darkened “rape dungeon” in an uncompromising show which is guaranteed to give even the most hardcore horror fans nightmares.

The first part of the Blackout waiver reads: “I have been advised and acknowledge that graphic scenes of simulated extreme horror, adult sexual content, tight spaces, darkness, fog, strobe light effects, exposure to water, physical contact, and crawling are an integral part of the experience of the House.”

One woman told Observer.com that she had a bag placed on her head before water was poured over her face while a man told her to "bark like a dog”.

She said: “Dude kept pouring water on my face when the bag was on my head, I couldn’t breathe, much less “bark like a real dog.”

“I was sucking wind and wet bag was clogging my mouth and nose, and I was hyperventilating.”

One of the events co-founders, Kristjan Thor, told The Wall Street Journal that the experience is partly influenced by the one of the final scenes in the movie Silence of the Lambs – where Jodie Foster's character hunts a serial killer in complete darkness.

He admitted that guests' reaction to the event can vary, adding: “Husbands and wives have had massive fights in the lobby.

"The husband comes out laughing. The wife comes out sobbing—'Why did you do this?'—and the husband has to do some damage control."

Sunny California appears to specialise in these morbidly dark experiences.

Heretic House is another LA haunt where claustrophobia is one of the key themes.

Customers have their clothes shredded, are covered in fake blood and nailed inside coffins.

A YouTube video shows a woman taking part in the terrifying ordeal.

She is told to put a mask on while standing in an almost pitch-black room before a group of burly men manhandle her and spray fake blood on her face.

In all the haunts, participants can use a “safe word” to end the experience.

The Victim Experience claims that 70 per cent of those taking part quit before the hour-long event is over.

While these increasingly popular attractions claim to only use psychological terror, blood has been spilled at an experience in Tennessee last week.

Last Friday, a man was stabbed in the arm outside the Nashville Nightmare Halloween attraction when his female friend was handed a knife by a stranger wearing a skull mask.

The woman told police she believed the blade was a prop when she knifed her pal when instructed by the mystery man.

A spokesperson for Nashville Nightmare said an employee has been placed on leave while an investigation into the incident continues, reports The Tennessean.

The victim named James Yochim was rushed to hospital and treated for a "severe laceration" on his arm.